NASA 1996 SBIR Phase I


PROPOSAL NUMBER : 96-1 13.06-4623

PROJECT TITLE : Large Aperture Multiplexed Diffractive Lidar ptics

TECHNICAL ABSTRACT (LIMIT 200 WORDS)

We propose a method of increasing the diameter of diffractive optics from 40 cm to 1 meter without scaling all of the fabrication equipment. Our prior work included fabrication of 40 cm gratings, some with a 1 meter focal length in both reflection and transmission configurations. We now are able to design and construct near IR HOEs with blue lasers and with appropriate alignment tooling believe we we can tile 7 to 9 40 cm elements together to make 1 meter elements on glass for wavelengths from 523 nm to 1064 nm. We present the design of a dual wavelength LIDAR optical system that uses 4 different Holographic surfaces to transmit, to collect to concentrate and to filter the return light.

We expect to be able to collect light in the visible and in the near IR with angular resolutions of 150 micro radians, which is similar to the 40 cm collectors made this year at 1064 nm. The diffraction efficiency of the 532 nm plates made thus far has been greater than 90%, neglecting fresnel reflections, while the best focusing 1064 plates have only reached about 80% because of increased absorption in the substrate and computer generated diffractive artifacts that can be largely illiminated in another innovative makeover.

The larger apertures are expected to enable longer range LIDAR applications of many kinds and because these HOEs are flat, relatively light weight and multifunctional, they may be ideal for orbiting missions. The support framework allows the use of lighter thin glass or plastcs.

POTENTIAL COMMERCIAL APPLICATIONS
Commercial LIDAR producers can also use our diffractive optics in their systems as needed and the same design and fabrication methods work for big photon buckets, medical imaging optics, fast spectrophotometers, solar collection and dispersion, solar laser pumping and architectural lighting.
NAME AND ADDRESS OF PRINCIPAL INVESTIGATOR
Richard D. Rallison PhD
Ralcon Development Lab
8501 S. 400 West box 142
Paradise UT 84328
NAME AND ADDRESS OF OFFEROR
Ralcon Development Lab
8501 S 400 West Box 142
Paradise UT 84328-0142